Lethal composition for insects



Reissued Jan. 25, 1949 LETHAL COMPOSITION FOR INSECTS Howard W. Eek, deceased, late of East Lansing, Mieh., by Lowell B. Kilgore and Helen Ford Kilgore, Washington, D. 0., Jared H. Ford, Kalamazoo, Mich.

assignees, and

No Drawing. Original No. 2,310,949, dated February 16, 1943, Serial No. 266,035, April 4, 1939. Application for reissue August 8, 1947, Serial 20 Claims. 1

This invention relates to a new composition of matter useful for killing insect pests such as flies, mosquitoes, moths, roaches and the like,

Most liquid contact insecticide sprays are an extract of pyrethrum flowers in a diluent vehicle such as a petroleum distillate. Such pyrethrum insecticide confronts a manufacturer with the necessity of importing, at considerable expense, a crude botanical, the active ingredients of which are unstable and variable. Such a hazardous source of supply, and of quality, coupled with attendant unpredictable fluctuations in price has been onerous to manufacturers of liquid contact insecticides who rely on pyrethrum for the principal active ingredient of their product. More recently, an insecticidal spray has been prepared synthetically by diluting a suitable organic thiocyanate. This however, introduces undesirable odors, especially at the higher concentrations now required for the so-called high kill" insecticides.

Contact sprays of pyrethrum or of organic thiccyanate are of a type to induce an initial paralytic efiect in insects, but they entail a disadvantage in that at an economic concentration the paralytic elfect so produced is only temporary in a large percentage of cases. Hence, a considerable number of the insects sprayed with such an insecticide completely recover.

To avoid this difiiculty andobtain the high kill demanded of a modern insecticidal spray, manufacturers have been forced to increase the concentration of these paralytic ingredients to a point where the cost of the spray produces a serious sales resistance.

' Hence, an object of our invention is to provide a chemical that will be compatible with the paralytic agents named as well as being capable of supplementing their insecticidal values. Another object is to provide chemicals of such insecticidal activity that a relatively small amount will replace a substantial or major amount of the paralytic agents now required to produce a satisfactory insecticidal spray. A special object of importance is to supplement paralytic agents of insecticidal sprays by new components that are of high lethal value to insects, More particularly, an object is to prepare a new insecticide of improved lethal or killing power. A further object is to provide chemical compounds of high lethal power, but practical for an insecticide. Also an object of our invention is to provide a chemical insecticide synthetically from readily available raw materials and at economical cost. This will render its use economically advisable in liquid insecticides and more particularly effect a substantial savings in replacing a substantive or major part of the pyrethrum or of the thiocyanate paralytic agents now required. Another object of our invention is to produce an insecticidal material that will have also satisfactory concomitant physical properties, such as freedom from odor, color, skin irritation and other un-- toward physiological effects on warm blooded animals. A special object, further, is the production of certain new and useful chemical compounds.

These and other objects will appear in the illustrated description of this invention more fully to be set forth, and defined in the appended claims. Attainment of these objects is a result of our discoveries concerning organic chemical compounds of an indandione type. These may be expressed in terms of their structural formula:

in which R is a hydrocarbon radical. We have discovered certain new chemical compounds of this formula, and also have found that all compounds of this type exhibit high lethal power for insects. Moreover, under this invention, small amounts of these lethal compounds exhibit such synergistic effect with the above paralyzing compounds, especially py ethrum, as to produce ex ceedingly useful insecticides, This invention utilizes small quantities of these indandione compounds with dilute solutions of pyrethrum extract to obtain an insecticide having the combined properties of rapid paralysis plus high killing power.

Under preferred practice of this invention appropriate quantities of these indandione compounds are distributed in a base for contacting insects. It will be illustrative to refer to pyrethrum extract dissolved in kerosene as a base, but without limitation either to pyrethrum or to kerosene, as other paralyzing chemicals are being developed and other solvents or also emulsified bases. These are typical of a paralyzing insecticide and a volatile solvent well known in this art; a 2.5% solution in kerosene of a 20:1 pyrethrum extract serves as an illustrative standard. Examples will serve to describe various compositions of this invention. In a preferred composition under this invention the indandione compound, 2-isovaieryl-1,3 indandione, is of out: standing value.

These examples are expressed in terms familiar in the art as knockdown and as kill power. They are evaluated according to present standard procedures, utilizing the so-called Peet-Grady method. In this a group of 100 flies is released within a gas chamber 6 X 6 x 6 feet; then 12cc. of the solution for test is sprayed into the chamber with a De Vilbiss atomizer, Special No, 5004. At the end of ten minutes the chamber is ventilated and the flies that have been knocked down are transferred to an observation cage and supplied with food. At the end of twenty-four hours the number of dead and living flies are determined. The number of flies on the floor or the chamber in minutes will hereinafter be designated as the knockdown and the number dead at the end of 24 hours as the kill.

It is well known that the resistance of house flies to insecticides varies widely. In order to compensate for this variation, concurrent checks in the resistance of the flies to standard pyrethrum insecticide were run on a group of 1,00 flies from the same cage as those used in testing the unknown sample. The order of the test was such that every unknown sample hada control group of 100 flies tested immediately before or mmediately after it. The standard pyrethrum insecticide used as a control was the oihcial test insecticide of the NationalAssociationoi Insecticide and DisinfectantL Ianuiacturers. This official test insecticide represents the average prodnot that is obtained by diluting one part of 2021 pyrethrum concentrate with nineteen parts of a deodorized kerosene having a boiling range of approximately 345 to 510 F.

The results obtained from a pair of tests, that is, one test on the unknown sample and one test on the official insecticide, were then adjusted statistically to the basis of a 50% kill for the oflicial test insecticide by the method published by one of us insoap magazine, June, 1937, page 116. Thus, if a pair of tests that were run on two groups of 100 flies taken from the same cage gave a 60% kill for the 0. T. I. and 90% kill for the sample, the adjusted kill for the sample on the basis of a 50% kill for the O. T. I. would be 85%. In the following tables all the figures for per cent kill are so adjusted.

EXAMPLE I The following table shows the kills which may be obtained by adding to solutions of 2 /2% :1 pyrethrum concentrate in deodorized kerosene various members of the series wherein R. is a hydrocarbon radical.

TABLE I 10 Min. 22%? Material and Concentration Knockdown 1 Percent Percent l 2.5% 20:1 pyrethrum concentrate 99.9 25 2... 2.5% 20:1 pyrethrum concentrate g./l00 cc. 2-Acetyl-l,3-indandione 100 46 3 2.5% 20:1 pyrethrum concentrate +0.5

g./l00 cc. z-propionyl-l ,S-indandiona. 100 so 4"." 25% 201 pyrethrum concentrate +05 g /l00 cc. 2-butyryl-l,3-indandione 100 73 5. 2.5% 201 pyrethrum concentrate +0.5

5./100 cc. 2-isobutyryi-l,3-indandionc 07. 5 (i5 0... 2.5% 201 pyrethrum concentrate +1.0

g./l00 cc.2-is0valeryl-l,S-indandione 100 7 2.5% 20.1 pyrethrum concentrate +0.5

g./l00c 2-isovaleryl-l,li-indandionc 100 59 8..." 2.5% 20:] pyrethrum concentrate +0.25

g./l00 cc.2-is0valeryl-l,B'indsmdiOne 300 7 9 25% 20:1 pyrethrum concentrate +0.5

g./l00 cc. 2n-.valeryl-l,3-indandi0ne 99. 6 T0 l0 2.5% 20:] pyrethrum concentrate +0.5

dione 100 11-... 2.5% 20 ethrum concentrate +0.5

g /l00 cc. 2-caproyl-l ,3-indandione 00 32. 2.5% 201 pyrethrum concentrate +0.5

g./l00 cc. 2 liexahydrobenzoyl-l,S-indandionc 100 61 l3 2.5% 201 pyrethrum concentrate +0.5

dione I. 09.0 42 14"" 2.5% 20:1 pyrethrum concentrate +0.5

g./100 cc. 2-benzoyl-1,3-indandione 100 55 15..-. 2.5% 20:1 pyrethrurnconcentrate +,l%

residue obtained from the Claisen condensation between dimethyl phthalate I and methyl isobutyl ketone as described in Example III 09. 9 03 16." 2.0 g./l00 cc. Z-isovaleryl-l,S-iudandione. 96

The above examples show the use of these compounds with pyrethrum, except that Exampics 1 and 16 are respectivelyfor pyrethrum alone and the indandione compound alone. The compounds when used alone are 'eiiective killing agents but are somewhat delayed in their action. In the last examplait; is to be noted that although the knockdown was inferior to the samples con-/ taining pyrethrum, the material killed practically all of the-flies that it knockeddown, while in the first example the 2.5% of20z1 pyrethrum concentrate gave acornplete knockdown but 75% of the flies recovered; The compounds are more useful when incorporated with a material such as pyrethrum which paralyzesthe'flies rapidly.

In these insecticides, lethalefiect is imparted generally .by indandione compounds of the formulawherein R is a butyl group generally; that is, normal butyl, .isobutyl, secondary butyl, or tertiary butyl.

The combination of these compounds with pyrethrum produces a synergistic .efiect, that is to say, more than the additive eiiect of the two ingredients. This effect may be demonstrated by using a paralyzing agent other than'the type of pyrethrum to obtain the rapid knockdown. Thus, in Table II, we have shown the results ofkill tests run on comparatively weak solutions of pyrethrum extract and B-butoxy-B-thiocyanodiethyl ether concentrate, said concentrate comprising approximately 50% of the active compound in kerosene. P-yrethrum .or fi-butoxy-p thiocyanodi-ethyl other when used by themselves give approximately the same kill. However, when an equal ammmt so: aune at! s51 seriesto each-'of the s'oititmn masmimarxe diffez eneedni'the kiilrpaw' -er:6iathem time. V buimyfi t 'killi'ng -s'tr engtho me mirmrefwasrmenelysafadi- :tlvewhile tn merease. synergistic effect w Taste- 11 are --.suitably prepared by -Claisen condensation between -an: estei -.of nethi'rl ketone, using ithe iusual lconH'ensk-ig agerits ior this Claisen oondensatidn isueh asta- LSO- clium or potassium orthir corresponding alcoi'dicate tthat ic'ompoimtl .is 2 isoizalerfl under this invention may beiprepared in similar 1 wherein :iR rts -a fihynrmi-bon: an

alkyl radical For example, we have prepared the compound 2-isovalery1-1,3-indandione (where R is the iso- -5 valeryl radical) by the following method:

EXAMPLE 11 A mixture of 194 parts (all parts given by "10 weight) dimethylgphthalate. and lflflspartsmetmll ..-isob11tyl ketone is .diluted wlth 400 ipaitts "Zlrfy lienzene and 23.. parts-Lei metallic s'odium ls dd'efl in'lsmallipieces. ""wlienitlietsodium hass ithenreaetion .mixtm'e is 'efitrac'teti' 'wlthiiw er varid m; the aqueous extrazetsa'eidi'fied. iAiyellow 'brown oil separates and crystallizes upon standing. Upon recrystallizationImethanol, a, light ,ye-llowesolii'melting at 6'7,., 1sobtained. Theron.- :bon hsidrogensanalysisi-amimeutral equivalen indanliione.

"Gamma-hydrogen afldlgsis-"Czilciilatd i'for CiZHiZOsZ carbolsi 73.00%. hfidrogen i62%. Found: eaibon 731.01% 'fhydre'g en "1611391).

iMoleczilar weight ('Rast).-'Calculajteli 230.. F0und1207.

"The structurafformma or iz lsovaleriill 'fi in- 2- 3 'tlahcllone is:

The other members'of the series of compounds manner. In some cases, Whereithe final compounds themselves were not/ei-ystalline, they were purified by recrystallizingitheirsalts (for exampie, sodium salts) and then} acidifying.

ll'ieiollowing. tablelists illustrative compounds 1 545i .fheiiseries holates.

An illustrative example is:

deseribd as inseatieidaisi inlExampleil theiikestones T irom em 31 were empered and ":th

astantiateithae bmaidf desrgnation dfiRaby-the term 0 mi'draearbon.

'iTABnaIII 7 command Ketime I a, .u. a. i out, v I.

- 'meehmmrmth iwowtkemeused. T-hiswas amixtnre embom 15% ntathyln'propyi ketrme andifityg meth ketone.

This invention is not restricted to the useot pure forms of compounds of the type The crude product obtained irom the Claise'n condensation of a dialkyl phthalate with a methyl ketone may be incorporated directly in an insecticide without isolating and purifying the pure compound. The following example will show how this may be donez.

11A mixture of '194 parts all parts given by weight) ,of dimethyl phthalate and 100 parts methyl isobutyl ketone is diluted with 400 parts of dry benzene,.and 23- parts of metallic sodium are added in small pieces. When the sodium has dissolved, the reaction mixture is agitated thoroughly with a slight excess of dilute acid. The benzene layer is separated, washed with water andthewet benzene removed under reduced pressure. 'One part of the resulting brown, sticky residue was shaken with 99 parts of petroleum distillate containing 2%% :1 pyrethrum concentrate. A small amount of insoluble material was filtered out and the resulting solution bioassayed by the Feet-Grady method. The resulting insecticide gave a 63% kill.

pounds of the type- "wherein R is a 'hydro'carbon'radical' are quite stable towards sunlight. It is well known that extracts of botanical insecticides such as pyrethrum, derris, cub and the like, are very unstable in the presence of sunlight and their effectiveness as insecticides is rapidly destroyed. The following example demonstrates the stability of our compounds:

EXAMPLE IV Two hundredicubic centimeters of deodorized kerosene .-containing. 2.0 grams of ,2-isovaleryl- 1,3;-

indandione were placed in'a bottle made of Corex :glass,'- a special glass which transmits a large percentage of the shorter wave lengths of light which have been found to be especially. destructive to pyrethrum and rotenone. The bottle was placedputdoors on the south side of the building; where it received the direct sunlight Whenever the weather was, clear. The bottle was allowed to remain outside from February 18- to- 3 ithis time 2 ofte was addedwIf 'no' the material would, that it did-before be ngii? March-120. At; he end 20: 1 pyrethrungi malice decomposition 1had '{o cc havefgiven the same nus; it is evident .th

Furthermore, we have found that the comt -these new insecticidals out of doors in .the sunlight; and for use on plants or trees where rotenone is unsatisfactory.=

In the foregoing description this invention has been illustrated by compositions in which petroleum distillates serve as distributing means or diluent for these -'new insecticidal materials. However, this invention is applicable also to use of other distributing means such as aqueous emulsions or organic emulsions, or also powders that may serve as distributing agents.

While this invention has been described by illustrative, preferred examples in accordance with the patent statutes; it will now be apparent to those skilled in this art that the principles of this invention may be embodied in other forms than those specifically set forth, but within the scope of the appended claims.

What we claim is:

1. An insecticide comprising an insect-paralyzing agent intermixed with acompound of the type CH--GR wherein Ris a. hydrocarbon radical, the compound "serving to impart lethal qualities to the insecticide.

2 An insecticide comprising an insect-paralyzing agent and a compound of the type-- wherein R. is a'butyl group, the compound serving to impartlethal quality to the insecticide.

3. An insecticidecomprising an insect-paralyzing agent and a compound of the type-- wherein R is the isobutyl groupy'the compound serving to impartfirewall/qualities to the insecticide.

4. An insecticide comprising py-rethrum and 2-isovaleryl-1,3-indandione, the indandione compound serving to impart lethal qualities to the insecticide.

5. An insecticidal composition of matter com prising a compound of the type:

wherein R is a butylgroup, the-compound serving to-impart-lethal qualities to the composition.

6. An insecticidal composition of matter comprising a compound of the type:

11 C (II) wherein R is a branched chain butyl group, the compound serving to impart lethal qualities to the composition.

7. An insecticidal composition of matter comprising 2-isovalery1-1,3-indandione, the compound serving to impart lethal qualities to the composition.

8. An insecticidal composition of matter comprising 2 trimethylacetyl 1,3 indandione, the compound serving to impart lethal qualities to the composition.

9. An insecticidal composition of matter comprising a compound of the type:

wherein R is a butyl group and a carrier therefor, the indandione compound serving to impart lethal qualities to the composition.

10. An insecticidal composition of matter comprising a compound of the type:

0 ll o CH i R wherein R is a branched chain butyl group and a carrier therefor, the indandione compound serving to impart lethal qualities to the composition.

11. An insecticidal composition of matter comprising a compound of the type:

wherein R is a butyl group, dissolved in kerosene, the indandione compound serving to impart lethal qualities to the composition.

12. An insecticide comprising an insect paralyzing agent and 2-trimethy1acetyl-1,3-indandione compound serving to impart lethal quality to the insecticide.

13. An insecticide comprising pyrethrum and 2-trimethylacety1-1,3-indandione, the indandione compound serving to impart lethal quality to the insecticide.

14. An insecticide comprising pyrethrum and a compound of the type:

10 wherein R is butyl, the indandione compound serving to impart lethal quality to the insecticide.

15. An insecticidal composition of matter comprising a compound of the type:

R @Nn.

wherein R is alkyl containing at least 4 carbon atoms, the compound serving to impart lethal qualities to the composition, and a carrier therefor.

16. An insecticidal composition of matter comprising a compound of the type:

wherein R is alkyl containin at least 4 carbon atoms, the compound serving to impart lethal qualities to the composition.

17. An insecticidal composition of matter comprising a compound of the type:

wherein R is amyl, the compound serving to impart lethal qualities to the composition.

18. An insecticidal composition of matter comprising, Z-n-caproyl-1,3-indandione, the compound serving to impart lethal qualities to the composition.

19. An insecticide comprising an insect paralyzing agent and a compound of the type:

wherein R is alkyl containing at least 4 carbon atoms, the compound serving to impart lethal qualities to the composition.

20. An insecticide comprising pyrethrum and a compound of the type:

wherein R is alkyl containing at least 4 carbon atoms, the compound serving to impart lethal qualities to the composition.

LOWELL B. KILGORE, HELEN FORD KILGORE, Assignees of Howard W. Eek, Deceased.

JARED H. FORD,

Co-in'ventor.

REFERENCES CITED The following references are of record in the file of this patent:

Schwerin-Berichte, 27, pages 104-107, 109, 110. 

